Does doing a lot of sport cause osteoarthritis?
This along with variations of the same question such as “I run, am I giving myself arthritis?” are really commonly asked questions. It seems logical that using a joint will cause wear and tear which will lead to osteoarthritis. After all we know that eventually the bearings and parts wear out in most mechanical items that we use a lot. However Bio-mechanics are not the same as mechanics
What is Osteoarthritis?
Osteoarthritis is what happens when the cartilage of joints starts to wear thin. The joint mechanics change and the soft tissue surrounding the joint can become irritated as a result. Our body interprets these changes as a threat to its overall status quo and over time starts to make permanent bony changes around the effected joint to help to protect it from further injury or insult. These changes are a bit like building a bony scaffolding around a joint to stiffen it up – after all its harder to injure a stiff joint because its harder to use it.
Are degenerative changes the same as osteoarthritis?
Not really; degenerative changes are what happen before osteoarthritis (the bony scaffolding) starts to happen. It is the early warning signs that something needs to be done. Degenerative changes can often be reversed with a bit of dedication. Osteoarthritis cannot be reversed but may be slowed down.
Doesn’t this mean that I should protect my joints?
Joints are made to move and take the body’s weight, all day, every day. So if you mean that you should protect your joints by using them, then the answer is yes!
A little bit of anatomy.
We do need to look a little at the anatomy of the joint to properly get it. In the simplest possible terms a joint is a moving part where two bones meet. The ends of the bones, where they articulate with each other, is covered in cartilage. Cartilage is smooth and slightly cushioned so that when weight is put on it it will compress slightly. What holds the two bones together as a joint does vary slightly from joint to joint but in the main there is always a joint capsule which is made of ligaments. This capsule doesn’t just hold the joint together it also stops the lubricating liquid from getting out (the inside of a joint should remain completely separate from the rest of the body for your entire life). This lubricating fluid (synovial fluid) is the only source of nutrition for your cartilage – there is no blood supply to cartilage, its the only tissue in the body that does not have a blood supply.
Why do I need to learn the anatomy?
Anatomy is important to know because when you understand it then you start to realise that the only way that cartilage can get nutrition is by imbibing it from the lubricating liquid in the joint. Putting weight on the joint can only be a good thing. When cartilage bears weight it compresses slightly. When the weight is removed cartilage springs back to shape. Being slightly porous it draws nutrition in as it returns to shape after compression. This needs to happen A LOT all throughout the day, every day. And it needs to happen to the whole cartilage surface of the joint. It is only through maintaining a healthy nutrition supply to cartilage that maintains its thickness and prevents degenerative changes that can lead to osteoarthritis.
Will being overweight cause me joint problems?
Only if you are inactive and do not load your joints on a very regular basis. Your joints will adapt to carrying extra weight and cope just fine. The only other reason that obesity may cause early degenerative changes to joints is through altered bio-mechanics – if the weight forces you to move in ways that are not optimal for your joints. This can lead to injury which could, if untreated lead to degenerative changes and osteoarthritis.
Why do some people who are very active get osteoarthritis then?
This will vary from person to person. The most likely reason for problems among those who have been very active is injury. Injury to a joint or around a joint can lead to altered bio-mechanics of the joint which may result in abnormal loading which can lead to problems if the problems persists for months or years.
Take home message.
Move! We need to be up and moving every half hour at least. If your work is office based take regular breaks. If you are binge watching Netflix take regular breaks. Walk at least 10,000 steps a day, dance, take up a sport. It doesn’t matter what you do as long as you move.